Which reaction is accompanied by the release of the greatest amount of energy?
(1) combustion of 10. g of propane
(2) electrolysis of 10. g of water
(3) nuclear fission of 10. g of uranium
(4) oxidation of 10. g of iron

the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.